Battery pack heating method, device and equipment based on motor winding and storage medium

Abstract

The invention discloses a battery pack heating method, device and equipment based on a motor winding, and a storage medium, relates to the technical field of battery thermal management, and discloses a battery pack heating method based on the motor winding, and the method comprises the steps: detecting the temperature of a rotor through a rotor operation state temperature model; when a heating instruction is received, at least two of bridge arm switches of a first phase, a second phase and a third phase of the power equipment are turned on according to the rotor temperature and the pipe opening strategy, and winding heating between different phases is carried out; transferring heat generated when the winding is heated to a battery pack; and stopping heating the winding according to a temperature protection strategy to complete heating of the battery pack. The heating process is accurately controlled by using a motor rotor temperature model, and heat is effectively transferred to the battery pack through heating of windings among different phases on the premise of ensuring safety, so that rapid preheating of the battery pack is completed.

Description

Technical Field

[0001] The present application relates to the field of battery thermal management technology, and in particular to a battery pack heating method, device, equipment and storage medium based on motor windings. Background Art

[0002] The performance of new energy vehicle power batteries is sensitive to temperature, and the battery performance is best at 15℃~35℃, so the power battery thermal management system must always control the battery temperature within an appropriate temperature range to maximize battery performance. The traditional battery pack heating design idea is to ensure that the battery pack works in a suitable temperature environment to maximize the driving range. Usually, a special electric heating PTC heater is used to generate heat on the surface of the battery pack or the heat of the heat pump air conditioner is brought to the battery pack through the cooling water in the waterway for heating.

[0003] However, using PTC heaters increases costs and may present safety risks from overheating. Air conditioning systems with heat pumps lose efficiency in cold environments and require an additional cooling mode to transfer heat. Using motor stall heating may damage the motor and control is not precise enough.

[0004] The above contents are only used to assist in understanding the technical solution of the present application and do not constitute an admission that the above contents are prior art. Summary of the invention

[0005] The main purpose of this application is to provide a battery pack heating method, device, equipment and storage medium based on motor windings, aiming to solve the technical problem of how to use existing motor windings to preheat the battery pack efficiently and accurately without increasing additional costs.

[0006] To achieve the above objectives, the present application proposes a battery pack heating method based on motor windings, the method comprising:

[0007] Detect the rotor temperature through the rotor operating state temperature model;

[0008] When a heating instruction is received, at least two of the bridge arm switches of the first phase, the second phase and the third phase of the power equipment are respectively opened according to the rotor temperature and the pipe opening strategy to heat the windings between different phases;

[0009] transferring heat generated when the winding is heated to the battery pack;

[0010] According to the temperature protection strategy, the winding heating is stopped and the battery pack heating is completed.

[0011] In one embodiment, when a heating instruction is received, the step of respectively opening at least two of the bridge arm switches of the first phase, the second phase, and the third phase of the power equipment according to the rotor temperature and the pipe opening strategy to heat the windings between different phases includes:

[0012] When a heating instruction is received, an open-tube time period is obtained according to the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, the negative temperature coefficient thermistor temperature, the current temperature of the battery pack, the proportional-integral-differential control strategy, and the open-tube heating strategy;

[0013] By using the opening tube strategy and the opening tube time period, at least two of the first upper bridge arm switch of the first phase, the first lower bridge arm switch of the first phase, the second upper bridge arm switch of the second phase, the second lower bridge arm switch of the second phase, the third upper bridge arm switch of the third phase and the third lower bridge arm switch of the third phase of the power equipment are opened to complete the heating of the windings between different phases.

[0014] In one embodiment, when a heating instruction is received, the step of obtaining the open-tube time period according to the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, the negative temperature coefficient thermistor temperature and the current temperature of the battery pack, the proportional-integral-differential control strategy and the open-tube heating strategy includes:

[0015] When a heating instruction is received, a rotor temperature control signal, an insulated gate bipolar transistor temperature control signal, a negative temperature coefficient thermistor temperature control signal and a battery pack current temperature control signal are obtained according to the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, the negative temperature coefficient thermistor temperature, the current temperature of the battery pack and a proportional-integral-differential control strategy;

[0016] Obtaining a target control signal according to the rotor temperature control signal, the insulated gate bipolar transistor temperature control signal, the negative temperature coefficient thermistor temperature control signal and the battery pack current temperature control signal;

[0017] According to the target control signal and the open-tube heating strategy, an open-tube time period is obtained.

[0018] In one embodiment, the step of completing the heating of the windings between different phases by opening at least two of the first upper bridge arm switch of the first phase, the first lower bridge arm switch of the first phase, the second upper bridge arm switch of the second phase, the second lower bridge arm switch of the second phase, the third upper bridge arm switch of the third phase, and the third lower bridge arm switch of the third phase of the power equipment through the opening tube strategy and the opening tube time period includes:

[0019] Open the first upper bridge arm switch and the second lower bridge arm switch of the power equipment through the open-tube strategy, and close the first lower bridge arm switch, the second upper bridge arm switch, the third upper bridge arm switch, and the third lower bridge arm switch;

[0020] When the on-time period has passed, closing the first upper bridge arm switch and the second lower bridge arm switch, and opening the first lower bridge arm switch and the second upper bridge arm switch;

[0021] When the on-time period has passed, closing the first lower bridge arm switch and the second upper bridge arm switch, and opening the second upper bridge arm switch and the third lower bridge arm switch;

[0022] When the on-time period has passed, closing the second upper bridge arm switch and the third lower bridge arm switch, and opening the second lower bridge arm switch and the third upper bridge arm switch;

[0023] When the on-time period has passed, closing the second lower bridge arm switch and the third upper bridge arm switch, and opening the third upper bridge arm switch and the first lower bridge arm switch;

[0024] When the on-tube time period has passed, the third upper bridge arm switch and the first lower bridge arm switch are turned off, and the third lower bridge arm switch and the first upper bridge arm switch are turned on to complete the heating of the windings between different phases.

[0025] In one embodiment, the step of detecting the rotor temperature by using the rotor operating state temperature model comprises:

[0026] Get the comprehensive power loss;

[0027] Establishing a rotor operating state temperature model according to the comprehensive power loss;

[0028] The rotor temperature is obtained according to the rotor operating state temperature model.

[0029] In one embodiment, the step of obtaining the comprehensive power loss includes:

[0030] Obtain coolant power loss, stator power loss to the environment, rotor and magnet power loss to the environment, and rotor heat loss;

[0031] The comprehensive power loss is obtained according to the stator power loss, the power loss dissipated by the stator to the environment, the power loss dissipated by the rotor and the magnetic steel to the environment, and the rotor heat loss.

[0032] In one embodiment, the step of obtaining the coolant power loss, the stator power loss to the environment, the rotor and magnetic steel power loss to the environment, and the rotor heat loss comprises:

[0033] The coolant power loss is obtained according to the coolant density, the cross-sectional area of ​​the cooling pipe, the coolant flow rate, the water inlet temperature and the water outlet temperature;

[0034] According to the stator surface convection heat transfer area, the stator surface temperature, the ambient temperature and the preset convection heat transfer coefficient, the dissipated power loss of the stator to the environment is obtained;

[0035] According to the convective heat transfer area of ​​the rotor surface, the rotor temperature at the first moment and the preset convective heat transfer coefficient, the power dissipation loss of the rotor and the magnetic steel to the environment is obtained;

[0036] The rotor heat loss is obtained according to the specific heat capacity of the rotor material, the rotor mass, the rotor temperature at the second moment and the rotor temperature at the third moment.

[0037] In one embodiment, the step of establishing a rotor operating state temperature model according to the comprehensive power loss comprises:

[0038] Obtaining the specific heat capacity of the stator material, the stator mass, the stator temperature at the first moment, and the stator temperature at the second moment;

[0039] A rotor operating state temperature model is established according to the specific heat capacity of the stator material, the stator mass, the stator temperature at the first moment, the stator temperature at the second moment, and the comprehensive power loss.

[0040] In one embodiment, the step of stopping the heating of the winding according to the temperature protection strategy and completing the heating of the battery pack includes:

[0041] Acquire a first preset temperature and a second preset temperature according to a temperature protection strategy, wherein the first preset temperature is greater than the second preset temperature;

[0042] When any one of the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, and the negative temperature coefficient thermistor temperature is greater than the first preset temperature or the current temperature of the battery pack is greater than the second preset temperature, the winding heating is stopped and the battery pack heating is completed.

[0043] In addition, to achieve the above-mentioned purpose, the present application also proposes a battery pack heating device based on a motor winding, and the battery pack heating device based on a motor winding includes:

[0044] A detection module, used for detecting the rotor temperature through a rotor operation state temperature model;

[0045] A heating module, configured to, upon receiving a heating instruction, respectively open at least two of the bridge arm switches of the first phase, the second phase and the third phase of the power equipment according to the rotor temperature and the pipe opening strategy, so as to heat the windings between different phases;

[0046] A transfer module, used for transferring heat generated when the winding is heated to a battery pack;

[0047] The stop module is used to stop the winding heating according to the temperature protection strategy and complete the battery pack heating.

[0048] In addition, to achieve the above-mentioned objectives, the present application also proposes a battery pack heating device based on motor windings, the device comprising: a memory, a processor, and a computer program stored on the memory and executable on the processor, the computer program being configured to implement the steps of the battery pack heating method based on motor windings as described above.

[0049] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by the processor, the steps of the battery pack heating method based on the motor winding are implemented as described above.

[0050] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, it implements the steps of the battery pack heating method based on motor windings as described above.

[0051] One or more technical solutions proposed in this application have at least the following technical effects:

[0052] The rotor temperature is detected by the rotor operating state temperature model; when receiving the heating instruction, at least two of the bridge arm switches of the first phase, the second phase and the third phase of the power equipment are opened respectively according to the rotor temperature and the open-tube strategy to heat the windings between different phases; the heat generated when the windings are heated is transferred to the battery pack; according to the temperature protection strategy, the winding heating is stopped to complete the technical means of heating the battery pack, which solves the problem of effectively preheating the battery pack without increasing the additional hardware cost, and achieves a fast and safe battery preheating effect. Compared with the existing technology, this solution optimizes the heating efficiency, improves the accuracy of temperature control, avoids potential damage to the motor and battery, and improves the performance and range of electric vehicles in low temperature environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0054] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0055] Figure 1 A schematic diagram of a flow chart provided in Embodiment 1 of the method for heating a battery pack based on motor windings of the present application;

[0056] Figure 2 A heating instruction sending logic diagram provided in Embodiment 1 of the method for heating a battery pack based on motor windings of the present application;

[0057] Figure 3 A schematic diagram of the electric drive system architecture provided in Embodiment 1 of the method for heating a battery pack based on motor windings of the present application;

[0058] Figure 4 A schematic diagram of a flow chart provided for Embodiment 2 of the method for heating a battery pack based on motor windings of the present application;

[0059] Figure 5 A block diagram of a powertrain control system provided in Embodiment 2 of the method for heating a battery pack based on motor windings of the present application;

[0060] Figure 6 A schematic diagram of a flow chart of Embodiment 3 of the method for heating a battery pack based on motor windings of the present application;

[0061] Figure 7 This is a schematic diagram of the module structure of a battery pack heating device based on motor windings according to an embodiment of the present application;

[0062] Figure 8 Schematic diagram of the device structure of the hardware operating environment involved in the battery pack heating method based on motor windings in the embodiment of the present application.

[0063] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0064] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0065] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0066] The main solution of the embodiment of the present application is: detecting the rotor temperature through a rotor operating state temperature model;

[0067] When a heating instruction is received, at least two of the bridge arm switches of the first phase, the second phase and the third phase of the power equipment are respectively opened according to the rotor temperature and the pipe opening strategy to heat the windings between different phases;

[0068] transferring heat generated when the winding is heated to the battery pack;

[0069] According to the temperature protection strategy, the winding heating is stopped and the battery pack heating is completed.

[0070] In this embodiment, for the convenience of description, the following description is made by taking the identification of the motor controller as the execution subject.

[0071] Since the existing technology cannot use the existing motor windings to preheat the battery pack efficiently and accurately without adding additional costs, the present application provides a solution, which uses the rotor operating state temperature model to detect the rotor temperature; when receiving the heating instruction, at least two of the bridge arm switches of the first phase, the second phase and the third phase of the power equipment are opened according to the rotor temperature and the open-tube strategy, and the windings between different phases are heated; the heat generated when the windings are heated is transferred to the battery pack; according to the temperature protection strategy, the winding heating is stopped, and the technical means of completing the battery pack heating solves the problem of effectively preheating the battery pack without adding additional hardware costs, and achieves a fast and safe battery preheating effect. Compared with the existing technology, this solution optimizes the heating efficiency, improves the accuracy of temperature control, and avoids potential damage to the motor and battery, improving the performance and range of electric vehicles in low temperature environments.

[0072] It should be noted that the execution subject of this embodiment can be a computing service device with data processing, network communication and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc., or an electronic device capable of realizing the above functions, a battery pack heating device based on motor windings, and a motor controller, etc. The motor controller is taken as an example to illustrate this embodiment and the following embodiments.

[0073] Based on this, the embodiment of the present application provides a battery pack heating method based on motor windings, referring to Figure 1 , Figure 1 This is a flow chart of the first embodiment of the battery pack heating method based on motor windings of the present application.

[0074] In this embodiment, the battery pack heating method based on the motor winding includes steps S10 to S40:

[0075] Step S10, detecting the rotor temperature through a rotor operating state temperature model;

[0076] It should be noted that the rotor operating state temperature model is a mathematical model used to describe the temperature change of the rotor during operation. This model needs to consider factors such as the motor load, ambient temperature, and physical properties of the rotor. The rotor temperature can be monitored in real time through the model to facilitate the use of the rotor temperature in subsequent steps.

[0077] In addition, it should be noted that the motor controller (MCU) is a key component for controlling the operation of the motor in the powertrain system of new energy vehicles. It is mainly responsible for receiving instructions from the vehicle control unit (VCU) or other control units, and accurately controlling the torque and speed of the motor to achieve vehicle starting, acceleration, deceleration and braking operations.

[0078] In a feasible implementation, step S10 may include steps S11 to S13:

[0079] Step S11, obtaining comprehensive power loss;

[0080] It should be noted that the comprehensive power loss refers to the power loss generated by multiple components such as coolant, stator, rotor and magnet during the operation of the motor.

[0081] It can be understood that the comprehensive power loss can measure the sum of energy losses caused by various factors during the operation of the motor. The comprehensive power loss includes coolant power loss, stator dissipation power loss to the environment, rotor and magnet dissipation power loss to the environment, and rotor heat loss. Coolant power loss refers to the heat absorbed by the coolant when it flows through the motor stator, which is related to the heat generated by the stator. The stator dissipation power loss to the environment involves the heat released by the stator and its windings to the environment through heat conduction, convection and radiation. The rotor and magnet dissipation power loss to the environment focuses on the heat released by the rotor and magnet to the environment through the heat exchange mechanism. Rotor heat loss refers to the heat generated by the rotor over a certain period of time due to its material properties and temperature changes.

[0082] In a feasible implementation, step S11 may include steps S111 to S112:

[0083] Step S111, obtaining the coolant power loss, the stator power loss to the environment, the rotor and magnetic steel power loss to the environment, and the rotor heat loss;

[0084] It should be noted that the coolant power loss is the stator power loss absorbed by the coolant, which indicates the heat absorbed by the coolant during the internal circulation of the motor, which is usually related to the heat generated by the stator. The stator's dissipated power loss to the environment includes the stator and its windings' dissipated power loss to the environment, indicating the heat released by the stator to the environment through heat conduction, convection and radiation. The rotor and magnet's dissipated power loss to the environment is the rotor and magnet's dissipated power loss to the surrounding environment, indicating the heat released by the rotor and magnet to the environment through similar heat exchange mechanisms. The rotor heat loss indicates the heat generated by the rotor in a certain period of time, which can be obtained through the rotor heat loss temperature model.

[0085] Step S112, obtaining a comprehensive power loss according to the stator power loss, the power loss dissipated by the stator to the environment, the power loss dissipated by the rotor and magnetic steel to the environment, and the rotor heat loss.

[0086] It is understood that the comprehensive power loss in the motor system is determined based on the various power loss parameters that have been obtained. Determination is to understand and describe the total heat loss of the motor during operation by analyzing and evaluating the impact of various parameters. The evaluation of stator power loss takes into account the resistance of the stator material and the heat generated when the current passes through. The stator dissipated power loss to the environment reflects the efficiency of the stator heat transfer to the surrounding environment, which is usually related to the design of the stator and the operating environment. The rotor and magnet dissipated power loss to the environment focuses on the heat release of the rotor and magnet. The calculation of rotor heat loss is based on the thermal characteristics of the rotor material and operating conditions, such as the specific heat capacity, mass and temperature change of the rotor.

[0087] In a feasible implementation, step S112 may include steps S1121 to S1124:

[0088] Step S1121, obtaining the coolant power loss according to the coolant density, the cross-sectional area of ​​the cooling pipe, the coolant flow rate, the water inlet temperature and the water outlet temperature;

[0089] It should be noted that the density of the coolant refers to the mass of the coolant per unit volume, which affects the heat capacity and heat transfer efficiency of the coolant. The cross-sectional area of ​​the cooling pipe, or the cross-sectional area of ​​the cooling line, refers to the area of ​​the cross-section of the pipe through which the coolant flows, which determines the flow rate and flow velocity of the coolant. The coolant flow velocity refers to the rate at which the coolant flows in the pipe, and the flow velocity affects the heat exchange efficiency between the coolant and the pipe wall. The water inlet temperature refers to the temperature of the coolant entering the motor cooling system, expressed in degrees Celsius (°C) or Kelvin (K). The water outlet temperature refers to the temperature of the coolant leaving the motor cooling system, also expressed in degrees Celsius (°C) or Kelvin (K).

[0090] It can be understood that the coolant power loss, i.e. the stator power loss absorbed by the coolant, is calculated as follows:

[0091] P ω =ρ ω C ω A ω υ(T in -T out )(Formula 1)

[0092] In the formula, ρ ω is the coolant density, C ω is the specific heat capacity of the coolant, A ω is the cross-sectional area of ​​the cooling pipe, υ is the flow velocity of the coolant, T in and T out are the inlet and outlet water temperatures, P ω is the stator power loss absorbed by the coolant.

[0093] Step S1122, obtaining the power dissipation loss of the stator to the environment according to the stator surface convection heat transfer area, the stator surface temperature, the ambient temperature and the preset convection heat transfer coefficient;

[0094] It should be noted that the stator surface convection heat transfer area refers to the area of ​​the stator surface involved in convection heat transfer. This area determines the efficiency of heat transfer. The larger the area, the stronger the heat dissipation capacity. The stator surface temperature refers to the temperature of the motor stator during operation, usually expressed in degrees Celsius (℃) or Kelvin (K). This temperature reflects the thermal state of the stator. The ambient temperature refers to the temperature of the environment surrounding the motor, also expressed in degrees Celsius (℃) or Kelvin (K). This temperature is a reference for heat dissipation. The convection heat transfer coefficient is a parameter that describes the efficiency of heat exchange between a fluid, such as air or coolant, and a solid surface. It depends on the properties, flow rate and flow state of the fluid.

[0095] It can be understood that the calculation formula of the power dissipation loss of the stator to the environment, that is, the power dissipation loss of the stator and its winding to the surrounding environment, is as follows:

[0096]

[0097] Where σ is the convective heat transfer coefficient, A s is the convective heat transfer area of ​​the stator and winding surface, T s is the surface temperature of the stator and winding, T 0 is the ambient temperature, which is a constant or obtained by sampling the controller, t 1 and t 2 They are the start and end time points within a unit of time, respectively, and are obtained by calculating the two PWM wave transmission time points.

[0098] In this embodiment, the convective heat transfer coefficient can be calculated using the empirical formula as follows:

[0099] σ=9.73+14V 0.62 (Formula 3)

[0100] In the formula, σ is the convection heat transfer coefficient, and V is the air flow velocity on the heat dissipation surface. When the rotor is stationary, σ=9.73.

[0101] Step S1123, obtaining the power dissipation loss of the rotor and the magnetic steel to the environment according to the convective heat transfer area of ​​the rotor surface, the rotor temperature at the first moment, and the preset convective heat transfer coefficient;

[0102] It should be noted that the rotor surface convection heat transfer area refers to the area of ​​the rotor surface involved in convection heat transfer. This area is the actual area where heat exchange occurs and has a direct impact on the heat dissipation efficiency. Rotor temperature at the first moment This is the rotor temperature measured at a specific point in time (the first moment), usually expressed in degrees Celsius (°C) or Kelvin (K). This temperature is the starting point for heat exchange calculations.

[0103] It can be understood that the power loss dissipated by the rotor and the magnetic steel to the environment, that is, the power loss dissipated by the rotor and the magnetic steel to the surrounding environment, is calculated as follows:

[0104]

[0105] In the formula, σ is the convective heat transfer coefficient, which is 9.73, A r is the convective heat transfer area of ​​the rotor surface, T r1 t 1 Rotor temperature at time t 1 and t 2 are the start and end time points in unit time respectively.

[0106] Step S1124, obtaining the rotor heat loss according to the specific heat capacity of the rotor material, the rotor mass, the rotor temperature at the second moment, and the rotor temperature at the third moment.

[0107] It should be noted that the specific heat capacity of the rotor material is an inherent property of the rotor material, which affects the amount of heat absorbed or released when its temperature changes. The rotor mass refers to the total mass of the rotor. The second moment rotor temperature is the rotor temperature measured at the second moment, and the third moment rotor temperature is the rotor temperature measured at a later third moment, which is used to compare with the temperature at the second moment to calculate the temperature change.

[0108] It can be understood that the formula of the rotor heat loss, that is, the rotor heat loss temperature model is as follows:

[0109]

[0110] In the formula, C r is the specific heat capacity of the rotor material, M r is the rotor mass, T r1 and T r2 are the rotor temperatures at the start and end time points per unit time, t 1 and t 2 are the start and end time points in unit time respectively.

[0111] Step S12, establishing a rotor operating state temperature model according to the comprehensive power loss;

[0112] It can be understood that the rotor operating state temperature model established based on the comprehensive power loss takes into account factors such as the motor load, ambient temperature, and physical properties of the rotor, and can more accurately monitor the temperature of the rotor in real time and can be conveniently used in subsequent steps.

[0113] In a feasible implementation, step S12 may include steps S121 to S122:

[0114] Step S121, obtaining the specific heat capacity of the stator material, the mass of the stator, the stator temperature at the first moment, and the stator temperature at the second moment;

[0115] It should be noted that the specific heat capacity of the stator material refers to the heat required per unit mass and unit temperature change of the stator material; the stator mass refers to the total mass of the motor stator, which affects its ability to store and release heat; the stator temperature at the first moment and the stator temperature at the second moment respectively represent the stator temperatures at the previous and next sampling time points, which are obtained through stator NTC sampling.

[0116] Step S122, establishing a rotor operating state temperature model according to the specific heat capacity of the stator material, the stator mass, the stator temperature at the first moment, the stator temperature at the second moment, and the comprehensive power loss.

[0117] It can be understood that the rotor operating state temperature model is as follows:

[0118]

[0119] In the formula, C s is the specific heat capacity of the stator material, M s is the stator mass, T S1 and T S2 are the stator temperature at the first moment and the stator temperature at the second moment, t 1 and t 2 is the sampling time point before and after. ω is the stator power loss absorbed by the coolant, P s_air is the power loss of the stator and its winding to the environment, P r_airP is the power loss of the rotor and magnetic steel to the surrounding environment, r is the rotor heat loss temperature model.

[0120] Step S13, obtaining the rotor temperature according to the rotor operating state temperature model.

[0121] It is understood that the real-time temperature of the rotor is calculated using the temperature model established in step S12 in combination with the real-time monitored power loss data. This temperature feedback can be used to monitor the thermal state of the system to ensure that the rotor operates within a safe and effective operating range or as a feedback signal to control the operation of the motor.

[0122] In addition, it can be understood that by substituting Formulas 1 to 5 into Formula 6, the following Formula 7 can be obtained:

[0123]

[0124] By rearranging the above formula 7, the rotor temperature can be obtained. The rotor temperature is calculated as follows:

[0125]

[0126] In the formula, at the start time, the rotor temperature T r1 =T r0 =T 0 , T 0 is the ambient temperature, T r2 is the rotor temperature.

[0127] Step S20, when a heating instruction is received, at least two of the bridge arm switches of the first phase, the second phase and the third phase of the power equipment are respectively opened according to the rotor temperature and the tube opening strategy to heat the windings between different phases;

[0128] It should be noted that the heating instruction is a signal sent from the VCU to instruct the start of the heating process.

[0129] Reference Figure 2 , Figure 2 This is a logic diagram of sending heating instructions for the first embodiment of the battery pack heating method based on motor windings of the present application.

[0130] like Figure 2As shown in the figure, after the start, the battery management system (BMS) controller detects that the battery pack temperature is lower than 10°C and sends a request for heating to the vehicle control unit (VCU). After the VCU receives the BMS request for heating, it forwards the request for heating to the MCU motor controller. After the MCU motor controller receives the heating command, the controller starts working; first determine whether the drive motor is working. If not, the drive motor and generator are heated by the MCU controller at the same time according to the IGBT temperature, stator NTC temperature, rotor temperature estimation and closed-loop control open-tube strategy, and the water circulation system is turned on to bring heat from the motor side of the motor controller to the battery pack; if the vehicle drive motor is working, the generator completes the heating process alone according to the IGBT temperature, stator NTC temperature, rotor temperature estimation and closed-loop control open-tube strategy.

[0131] In addition, it should be noted that the power equipment refers to a generator or a drive motor and a generator.

[0132] It should be noted that phase refers to three independent AC circuits, which are marked as U phase, V phase and W phase. Among them, the first phase, the second phase and the third phase represent the U phase, the V phase and the W phase respectively. The bridge arm switch refers to the power electronic switching device in the motor controller, such as the insulated gate bipolar transistor, which forms a full-bridge or half-bridge circuit to control the flow of current and the path from the power supply to the motor.

[0133] It is understandable that when the motor winding is energized, the current passing through the winding will generate heat due to the existence of resistance. In this embodiment, the winding heating is achieved by controlling the IGBT or other switching devices of the motor so that it generates heat without generating mechanical movement.

[0134] Step S30, transferring the heat generated when the winding is heated to the battery pack;

[0135] It is understandable that the motor usually has a water circulation system to dissipate heat. The water circulation system needs to be opened, the coolant absorbs the heat generated by the winding, and then the hot coolant is transported to the battery pack through a pump. The heat is transferred to the battery pack through a heat exchanger, which can steadily increase the temperature of the battery pack.

[0136] Reference Figure 3 , Figure 3 This is a schematic diagram of the electric drive system architecture of the first embodiment of the battery pack heating method based on motor windings of the present application.

[0137] like Figure 3As shown in the figure, it includes two main parts: the electric drive system and the power battery pack. The electric drive system is connected to the power battery pack through a high-voltage power supply circuit, and the motor control unit is responsible for controlling the operation of the motor unit. The power battery pack is cooled by the power battery cooling circuit, which contains cooling water pipes. In addition, the electric drive system also has a special cooling circuit to maintain heat transfer. The temperature collection point, motor winding and motor rotor position are also identified.

[0138] Step S40: According to the temperature protection strategy, the winding heating is stopped to complete the battery pack heating.

[0139] It should be noted that the temperature protection strategy is a set of safety measures used to monitor and control the temperature of the battery pack and motor windings to prevent the battery pack from overheating during the heating process to prevent damage to the battery pack.

[0140] This embodiment provides a battery pack heating method based on motor windings. By establishing and applying a rotor operating state temperature model, combined with real-time monitoring of coolant power loss, stator dissipation power loss to the environment, rotor and magnet dissipation power loss to the environment, and rotor heat loss and other parameters, the heating process of the motor windings is accurately controlled, solving the technical problem of how to efficiently and safely use the heat generated by the motor windings to preheat the battery pack without adding additional hardware costs. Through precise temperature control and temperature protection strategies, this method not only improves the performance of the battery pack in low temperature environments and the cruising range of electric vehicles, but also avoids the risk of damage to the battery pack and motor due to overheating, achieving the beneficial effect of optimizing the thermal management system of electric vehicles.

[0141] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be repeated in the following. Figure 4 , step S20 of the battery pack heating method based on motor windings further includes steps S21-S22:

[0142] Step S21, when a heating instruction is received, an open-tube time period is obtained according to the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, the negative temperature coefficient thermistor temperature, the current temperature of the battery pack, the proportional-integral-differential control strategy, and the open-tube heating strategy;

[0143] It should be noted that the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches is the IGBT temperature. IGBT is a key component in the motor controller for controlling the flow of current. Their operating temperature affects the thermal management and control strategy of the motor.

[0144] Please refer to Figure 5 , Figure 5It is a block diagram of a powertrain control system of the second embodiment of the battery pack heating method based on motor windings of the present application.

[0145] like Figure 5 As shown in FIG. 1 , the powertrain control system includes the motor M, the motor controller MCU, the high-voltage DC bus DC connected to the controller, the ground GND, the three-phase output lines (U, V, W) of the motor, the upper and lower bridge arms (U upper, U lower, V upper, V lower, W upper, W lower) that control the switches of U, V, and W respectively, and the IGBT switch devices (gut, gub, gvt, gvb, gwt, gwb) related to each phase in the motor controller, where gut is the upper bridge arm switch device that controls the U phase; gub is the lower bridge arm switch device that controls the U phase; gvt is the upper bridge arm switch device that controls the V phase; gvb is the lower bridge arm switch device that controls the V phase; gwt is the upper bridge arm switch device that controls the W phase; gwb is the lower bridge arm switch device that controls the W phase, and the corresponding control signal lines for controlling the motor operation state. The powertrain control system is designed for new energy vehicles, and realizes efficient driving and energy management of the vehicle by accurately controlling the torque and speed of the motor.

[0146] In addition, it should be noted that the negative temperature coefficient thermistor (NTC) temperature is the NTC temperature. NTC is a temperature sensor whose resistance decreases as the temperature increases. It is usually used to monitor the temperature of the motor stator or other components. The current temperature of the battery pack represents the real-time temperature of the battery pack, which is an important factor in determining whether heating is required and the degree of heating. The proportional-integral-differential (PID) control strategy is the PID control algorithm. The PID control algorithm is a feedback control strategy used to calculate the control signal to reduce the deviation between the system output and the expected value. The proportional (P) responds to the current deviation, the integral (I) responds to the accumulated deviation, and the differential (D) predicts future changes in the deviation. The open tube heating strategy is a control strategy used to determine when and how to operate the IGBT of the motor to control the heating of the motor windings.

[0147] In a feasible implementation, step S21 may include steps S211 to S213:

[0148] Step S211, when a heating instruction is received, a rotor temperature control signal, an insulated gate bipolar transistor temperature control signal, a negative temperature coefficient thermistor temperature control signal and a battery pack current temperature control signal are obtained according to the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, the negative temperature coefficient thermistor temperature, the current temperature of the battery pack and a proportional-integral-differential control strategy;

[0149] It can be understood that the rotor temperature control signal, the insulated gate bipolar transistor temperature control signal, the negative temperature coefficient thermistor temperature control signal and the battery pack current temperature control signal are the outputs obtained by inputting the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, the negative temperature coefficient thermistor temperature, and the battery pack current temperature into the proportional-integral-differential control algorithm.

[0150] In addition, it can be understood that the calculation formula of the rotor temperature control signal, the insulated gate bipolar transistor temperature control signal, the negative temperature coefficient thermistor temperature control signal and the battery pack current temperature control signal is as follows:

[0151] △t(k)=K p ×[t(k)-t(k-1)]+K i ×t(k)+K d ×[t(k)-2t(k-1)+t(k-2)](Formula 9)

[0152] In the formula, K p is the proportional gain, K p Inversely proportional to the proportionality, K i is the integration coefficient, K d is the differential coefficient. △t(k) is the output signal of the PID controller, including △t(k) igbt , Δt(k) Ts , Δt(k) Tr2 and Δt(k) Tbattery , where Δt(k) Tr2 is the rotor temperature control signal, Δt(k) igbt is the insulated gate bipolar transistor temperature control signal, Δt(k) Ts is the temperature control signal of the negative temperature coefficient thermistor, Δt(k) Tbattery is the current temperature control signal of the battery pack. t(k) is the IGBT temperature T at time k igbt , Motor stator NTC temperature T s , rotor online estimated temperature T r2 、Current battery pack temperature T battery ; t(k-1) is the IGBT temperature T at the previous moment k-1 igbt , Motor stator NTC temperature T s , rotor online estimated temperature T r2 、Current battery pack temperature T battery The IGBT temperature, motor stator NTC temperature, and battery pack current temperature can be obtained by MCU AD sampling and table lookup.

[0153] Step S212, obtaining a target control signal according to the rotor temperature control signal, the insulated gate bipolar transistor temperature control signal, the negative temperature coefficient thermistor temperature control signal and the battery pack current temperature control signal;

[0154] It is understandable that comparing Δt(k) igbt , Δt(k) Ts , Δt(k) Tr2 and Δt(k) Tbattery The maximum value Δt(k) is obtained Max , this maximum value Δt(k) Max That is the target control signal.

[0155] Step S213, obtaining the tube opening time period according to the target control signal and the tube opening heating strategy.

[0156] It should be noted that the open-tube heating strategy is a set of predefined rules or algorithms for determining the on and off of power electronic devices such as IGBTs in the motor controller to achieve heating of the motor windings. The open-tube time period is a time interval calculated based on the target control signal and the open-tube heating strategy. During this time period, certain bridge arm switches of the motor will be activated for heating. In this embodiment, the open-tube time period can be obtained by the time width of a single wave pulse.

[0157] In addition, it should be noted that the time width of a single wave pulse usually refers to the conduction time of a switch device (such as a transistor, IGBT, etc.) within a PWM (pulse width modulation) control cycle. This time width is also called pulse width or duty cycle, which determines the time ratio of the switch device in the on state within a PWM cycle. In this embodiment, the wave frequency is 10kHz, that is, the period of a single wave pulse is 100us.

[0158] It can be understood that the open tube heating strategy represents the relationship between the single open tube pulse width t and the PID feedback amount Δt(k) at a 10kHz wave frequency. The larger the PID feedback amount, the larger the pulse width, and the smaller the PID feedback amount, the smaller the pulse width. The calculation of the single open tube pulse width is as follows:

[0159] t=ζ*Δt(k),t≤98us(Formula 10)

[0160] Where ζ is a constant, which is set by the software and the most suitable value is selected through multiple experimental calibrations; Δt(k) is the PID feedback value. In this embodiment, Δt(k) needs to be Max Substitute into formula 10 for calculation.

[0161] Step S22, through the opening strategy and the opening time period, at least two of the first upper bridge arm switch of the first phase, the first lower bridge arm switch of the first phase, the second upper bridge arm switch of the second phase, the second lower bridge arm switch of the second phase, the third upper bridge arm switch of the third phase and the third lower bridge arm switch of the third phase of the power equipment are opened to complete the heating of the windings between different phases.

[0162] It should be noted that the first upper bridge arm switch (gut) and the first lower bridge arm switch (gub) of the first phase are switching devices that control the U-phase current of the motor, usually using IGBT or other types of power electronic devices. The coordinated work of the upper bridge arm and the lower bridge arm controls the direction and magnitude of the current. The second upper bridge arm switch (gvt) and the second lower bridge arm switch (gvb) of the second phase also control the current of the V phase, and the activation mode of these switching devices determines the current state of the V phase. The third upper bridge arm switch (gwt) and the third lower bridge arm switch (gwb) of the third phase control the current of the W phase to complete the three-phase control of the three-phase motor.

[0163] It is understood that during the determined on-time period, a signal is sent through the motor controller to activate the selected bridge arm switch, which causes current to flow through the motor winding, and due to the existence of resistance, the current generates heat, thereby heating the winding.

[0164] In a feasible implementation, step S22 may include steps S221 to S226:

[0165] Step S221, opening the first upper bridge arm switch and the second lower bridge arm switch of the power equipment through the open-tube strategy, and closing the first lower bridge arm switch, the second upper bridge arm switch, the third upper bridge arm switch and the third lower bridge arm switch;

[0166] Step S222, when the on-time period has passed, closing the first upper bridge arm switch and the second lower bridge arm switch, and opening the first lower bridge arm switch and the second upper bridge arm switch;

[0167] Step S223, when the on-time period has passed, closing the first lower bridge arm switch and the second upper bridge arm switch, and opening the second upper bridge arm switch and the third lower bridge arm switch;

[0168] Step S224, when the on-time period has passed, closing the second upper bridge arm switch and the third lower bridge arm switch, and opening the second lower bridge arm switch and the third upper bridge arm switch;

[0169] Step S225, when the on-time period has passed, closing the second lower bridge arm switch and the third upper bridge arm switch, and opening the third upper bridge arm switch and the first lower bridge arm switch;

[0170] Step S226, when the on-time period has passed, the third upper bridge arm switch and the first lower bridge arm switch are turned off, and the third lower bridge arm switch and the first upper bridge arm switch are turned on to complete the heating of the windings between different phases.

[0171] It can be understood that steps S221 to S226 represent an open-tube strategy. In this embodiment, the open-tube strategy is that the MCU is powered on, the high-voltage bus DC is powered on, and the six bridge arms gut, gub, gvt, gvb, gwt, and gwb are in the off state; gut / gvb is turned on to heat the winding between UV; gub / gvt / gwt / gwb is turned off; after a dead time of 2us; gub / gvt is turned on; the winding between UV is heated; gut / gvb / gwt / gwb is turned off; after a dead time of 2us; gvt / gwb is turned on to heat the winding between VW; gut / gub / gvb / gwt is turned off; after a dead time of 2us; gvb / gwt is turned on to heat the winding between VW; gut / gub / gvt / gwb is turned off; after a dead time of 2us; gwt / gub is turned on to heat the winding between UW; gut / gvt / gvb / gwb is turned off; after a dead time of 2us; gwb / gut is turned on to heat the winding between UW; gub / gvt / gvb / gwt is turned off.

[0172] In addition, it can be understood that the control process of the cyclic repeated opening tube strategy has a wave frequency of 10kHz, that is, a single wave pulse period of 100us, while monitoring the temperature of the battery pack and setting the target temperature to 35°C. When the target temperature is reached, the repeated opening tube strategy is stopped.

[0173] This embodiment provides a battery pack heating method based on motor windings. By applying a proportional-integral-differential control strategy (PID) and an accurate open-tube heating strategy, combined with real-time monitoring of the rotor temperature, IGBT temperature, NTC temperature, and current battery pack temperature, accurate control of the motor winding heating process is achieved. By dynamically adjusting the on-time of the switching device (such as IGBT), that is, adjusting the duty cycle of PWM, the technical problem of how to efficiently and safely use the heat generated by the motor windings to preheat the battery pack without adding additional hardware costs is solved. The beneficial effects of optimizing the performance of electric vehicles in low temperature environments, improving the heating efficiency of the battery pack, and ensuring that the battery pack and the motor operate within a safe temperature range are achieved, thereby extending their service life and improving the overall system energy efficiency.

[0174] Based on the first embodiment of the present application, in the third embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be repeated in the following. Figure 6After step S40, the battery pack heating method based on the motor winding further includes steps S41 to S42:

[0175] Step S41, obtaining a first preset temperature and a second preset temperature according to a temperature protection strategy, wherein the first preset temperature is greater than the second preset temperature;

[0176] It should be noted that the first preset temperature refers to a higher safety temperature threshold set in the temperature protection strategy. When the temperature of any one of the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, and the negative temperature coefficient thermistor temperature reaches this value, the heating source will be turned off. The second preset temperature represents the maximum temperature of the battery pack heating.

[0177] In this embodiment, the first preset temperature is 100°C, and the second preset temperature is 35°C.

[0178] Step S42, when any one of the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, and the negative temperature coefficient thermistor temperature is greater than the first preset temperature or the current temperature of the battery pack is greater than the second preset temperature, stop the winding heating and complete the battery pack heating.

[0179] It can be understood that if any of the rotor temperature, IGBT temperature or NTC temperature exceeds the first preset temperature, or the current temperature of the battery pack exceeds the second preset temperature, it is considered that the heating demand has been met or there is a risk of overheating, and an instruction needs to be sent to the motor controller to stop the heating process of the winding. After the winding heating stops, the battery pack heating process is completed.

[0180] The present embodiment provides a battery pack heating method based on the motor winding of the present application. By applying a temperature protection strategy, two key temperature thresholds are set (the first preset temperature is 100°C, and the second preset temperature is 35°C). The real-time monitoring of the rotor temperature, IGBT temperature, NTC temperature and the current temperature of the battery pack is utilized, and the heating is automatically stopped when any temperature exceeds these preset values. The technical difficulty of how to effectively avoid overheating problems during the battery pack heating process is solved, and the beneficial effects of ensuring that the battery pack and the motor operate within a safe temperature range, preventing thermal damage, improving system reliability and extending battery life are achieved.

[0181] This application also provides a battery pack heating device based on motor windings, please refer to Figure 7 , the battery pack heating device based on motor windings includes:

[0182] A detection module 10, used to detect the rotor temperature through a rotor operating state temperature model;

[0183] The heating module 20 is used to, upon receiving a heating instruction, respectively open at least two of the bridge arm switches of the first phase, the second phase and the third phase of the power equipment according to the rotor temperature and the pipe opening strategy to heat the windings between different phases;

[0184] A transfer module 30, used to transfer the heat generated when the winding is heated to the battery pack;

[0185] The stop module 40 is used to stop the winding heating according to the temperature protection strategy to complete the battery pack heating.

[0186] The battery pack heating device based on motor windings provided in the present application adopts the battery pack heating method based on motor windings in the above-mentioned embodiment, which can solve the technical problem of how to use the existing motor windings to preheat the battery pack efficiently and accurately without adding additional costs. Compared with the prior art, the beneficial effects of the battery pack heating device based on motor windings provided in the present application are the same as the beneficial effects of the battery pack heating method based on motor windings provided in the above-mentioned embodiment, and the other technical features of the battery pack heating device based on motor windings are the same as the features disclosed in the above-mentioned embodiment method, which will not be repeated here.

[0187] In one embodiment, the heating module 20 is also used to obtain an open-tube time period based on the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, the negative temperature coefficient thermistor temperature and the current temperature of the battery pack, the proportional-integral-differential control strategy and the open-tube heating strategy when a heating instruction is received; and open at least two of the first upper bridge arm switch of the first phase, the first lower bridge arm switch of the first phase, the second upper bridge arm switch of the second phase, the second lower bridge arm switch of the second phase, the third upper bridge arm switch of the third phase and the third lower bridge arm switch of the third phase of the power equipment through the open-tube strategy and the open-tube time period to complete winding heating between different phases.

[0188] In one embodiment, the heating module 20 is also used to obtain a rotor temperature control signal, an insulated gate bipolar transistor temperature control signal, a negative temperature coefficient thermistor temperature control signal and a current battery pack temperature control signal according to the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, the negative temperature coefficient thermistor temperature, the current battery pack temperature and the proportional-integral-differential control strategy when a heating instruction is received; obtain a target control signal according to the rotor temperature control signal, the insulated gate bipolar transistor temperature control signal, the negative temperature coefficient thermistor temperature control signal and the current battery pack temperature control signal; and obtain an open-tube time period according to the target control signal and the open-tube heating strategy.

[0189] In one embodiment, the heating module 20 is also used to open the first upper bridge arm switch and the second lower bridge arm switch of the power equipment through the open-tube strategy, and close the first lower bridge arm switch, the second upper bridge arm switch, the third upper bridge arm switch and the third lower bridge arm switch; when the open-tube time period passes, close the first upper bridge arm switch and the second lower bridge arm switch, and open the first lower bridge arm switch and the second upper bridge arm switch; when the open-tube time period passes, close the first lower bridge arm switch and the second upper bridge arm switch, and open the second upper bridge arm switch and the third lower bridge arm switch; when the open-tube time period passes, close the second upper bridge arm switch and the third lower bridge arm switch, and open the second lower bridge arm switch and the third upper bridge arm switch; when the open-tube time period passes, close the second lower bridge arm switch and the third upper bridge arm switch, and open the third upper bridge arm switch and the first lower bridge arm switch; when the open-tube time period passes, close the third upper bridge arm switch and the first lower bridge arm switch, and open the third lower bridge arm switch and the first upper bridge arm switch, so as to complete the heating of the windings between different phases.

[0190] In one embodiment, the detection module 10 is also used to establish a rotor operating state temperature model; obtain coolant power loss, stator dissipation power loss to the environment, rotor and magnetic steel dissipation power loss to the environment, and rotor heat loss; obtain the rotor temperature according to the stator power loss, the stator dissipation power loss to the environment, the rotor and magnetic steel dissipation power loss to the environment, the rotor heat loss and the rotor operating state temperature model.

[0191] In one embodiment, the detection module 10 is further used to obtain the coolant power loss according to the coolant density, the cooling pipe cross-sectional area, the coolant flow rate, the water inlet temperature and the water outlet temperature; to obtain the dissipated power loss of the stator to the environment according to the stator surface convection heat transfer area, the stator surface temperature, the ambient temperature and the preset convection heat transfer coefficient; to obtain the dissipated power loss of the rotor and the magnetic steel to the environment according to the rotor surface convection heat transfer area, the rotor temperature at the first moment and the preset convection heat transfer coefficient; to obtain the rotor heat loss according to the specific heat capacity of the rotor material, the rotor mass, the rotor temperature at the second moment and the rotor temperature at the third moment.

[0192] In one embodiment, the stop module 40 is also used to obtain a first preset temperature and a second preset temperature according to a temperature protection strategy, and the first preset temperature is greater than the second preset temperature; when any one of the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, and the negative temperature coefficient thermistor temperature is greater than the first preset temperature or the current temperature of the battery pack is greater than the second preset temperature, the winding heating is stopped and the battery pack heating is completed.

[0193] The present application provides a battery pack heating device based on a motor winding, and the battery pack heating device based on a motor winding includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the battery pack heating method based on the motor winding in the above-mentioned embodiment one.

[0194] Reference below Figure 8 , which shows a schematic diagram of the structure of a battery pack heating device based on motor windings suitable for implementing the embodiment of the present application. The battery pack heating device based on motor windings in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 8 The motor winding-based battery pack heating device shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0195] like Figure 8As shown, the battery pack heating device based on the motor winding may include a processing device 1001 (such as a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM: Read Only Memory) 1002 or the program loaded from the storage device 1003 to the random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the battery pack heating device based on the motor winding are also stored. The processing device 1001, ROM1002 and RAM1004 are connected to each other through a bus 1005. The input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; storage devices 1003 including, for example, a magnetic tape, a hard disk, etc.; and communication devices 1009. The communication device 1009 can allow the motor winding-based battery pack heating device to communicate wirelessly or wired with other devices to exchange data. Although the figure shows a motor winding-based battery pack heating device with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems may be implemented or have alternatively.

[0196] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0197] The battery pack heating device based on motor windings provided in the present application adopts the battery pack heating method based on motor windings in the above embodiment, which can solve the technical problem of how to use the existing motor windings to preheat the battery pack efficiently and accurately without adding additional costs. Compared with the prior art, the beneficial effects of the battery pack heating device based on motor windings provided in the present application are the same as the beneficial effects of the battery pack heating method based on motor windings provided in the above embodiment, and the other technical features of the battery pack heating device based on motor windings are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0198] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0199] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0200] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the battery pack heating method based on motor windings in the above-mentioned embodiment.

[0201] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0202] The above-mentioned computer-readable storage medium may be included in the battery pack heating device based on the motor winding; or it may exist independently without being assembled into the battery pack heating device based on the motor winding.

[0203] The above-mentioned computer-readable storage medium carries one or more programs. When the above-mentioned one or more programs are executed by a battery pack heating device based on a motor winding, the battery pack heating device based on a motor winding: detects the rotor temperature through a rotor operating state temperature model; upon receiving a heating instruction, opens at least two of the bridge arm switches of the first phase, the second phase and the third phase of the power equipment according to the rotor temperature and the open-tube strategy, and performs winding heating between different phases; transfers the heat generated during the heating of the winding to the battery pack; and stops the winding heating according to the temperature protection strategy to complete the battery pack heating.

[0204] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0205] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0206] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0207] The readable storage medium provided in the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned battery pack heating method based on motor windings, and can solve the technical problem of how to use existing motor windings to preheat the battery pack efficiently and accurately without adding additional costs. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in the present application are the same as the beneficial effects of the battery pack heating method based on motor windings provided in the above-mentioned embodiments, and will not be repeated here.

[0208] The present application also provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the above-mentioned battery pack heating method based on motor windings.

[0209] The computer program product provided by the present application can solve the technical problem of how to use the existing motor windings to preheat the battery pack efficiently and accurately without adding additional costs. Compared with the prior art, the beneficial effects of the computer program product provided by the present application are the same as the beneficial effects of the battery pack heating method based on the motor windings provided in the above embodiment, which will not be repeated here.

[0210] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A battery pack heating method based on motor windings, characterized in that: The method comprises: Detect the rotor temperature through the rotor operating state temperature model; When a heating instruction is received, at least two of the bridge arm switches of the first phase, the second phase and the third phase of the power equipment are respectively opened according to the rotor temperature and the pipe opening strategy to heat the windings between different phases; transferring heat generated when the winding is heated to the battery pack; According to the temperature protection strategy, the winding heating is stopped and the battery pack heating is completed.

2. The method according to claim 1, characterized in that The step of respectively opening at least two of the bridge arm switches of the first phase, the second phase and the third phase of the power equipment according to the rotor temperature and the pipe opening strategy upon receiving the heating instruction to heat the windings between different phases comprises: When a heating instruction is received, an open-tube time period is obtained according to the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, the negative temperature coefficient thermistor temperature, the current temperature of the battery pack, the proportional-integral-differential control strategy, and the open-tube heating strategy; By using the opening tube strategy and the opening tube time period, at least two of the first upper bridge arm switch of the first phase, the first lower bridge arm switch of the first phase, the second upper bridge arm switch of the second phase, the second lower bridge arm switch of the second phase, the third upper bridge arm switch of the third phase and the third lower bridge arm switch of the third phase of the power equipment are opened to complete the heating of the windings between different phases.

3. The method according to claim 2, characterized in that When receiving the heating instruction, the step of obtaining the open-tube time period according to the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, the negative temperature coefficient thermistor temperature and the current temperature of the battery pack, the proportional-integral-differential control strategy and the open-tube heating strategy includes: When a heating instruction is received, a rotor temperature control signal, an insulated gate bipolar transistor temperature control signal, a negative temperature coefficient thermistor temperature control signal and a battery pack current temperature control signal are obtained according to the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, the negative temperature coefficient thermistor temperature, the current temperature of the battery pack and a proportional-integral-differential control strategy; Obtaining a target control signal according to the rotor temperature control signal, the insulated gate bipolar transistor temperature control signal, the negative temperature coefficient thermistor temperature control signal and the battery pack current temperature control signal; According to the target control signal and the open-tube heating strategy, an open-tube time period is obtained.

4. The method according to claim 2, characterized in that The step of heating the windings between different phases by opening at least two of the first upper bridge arm switch of the first phase, the first lower bridge arm switch of the first phase, the second upper bridge arm switch of the second phase, the second lower bridge arm switch of the second phase, the third upper bridge arm switch of the third phase, and the third lower bridge arm switch of the third phase of the power equipment through the opening strategy and the opening time period includes: Open the first upper bridge arm switch and the second lower bridge arm switch of the power equipment through the open-tube strategy, and close the first lower bridge arm switch, the second upper bridge arm switch, the third upper bridge arm switch, and the third lower bridge arm switch; When the on-time period has passed, closing the first upper bridge arm switch and the second lower bridge arm switch, and opening the first lower bridge arm switch and the second upper bridge arm switch; When the on-time period has passed, closing the first lower bridge arm switch and the second upper bridge arm switch, and opening the second upper bridge arm switch and the third lower bridge arm switch; When the on-time period has passed, closing the second upper bridge arm switch and the third lower bridge arm switch, and opening the second lower bridge arm switch and the third upper bridge arm switch; When the on-time period has passed, closing the second lower bridge arm switch and the third upper bridge arm switch, and opening the third upper bridge arm switch and the first lower bridge arm switch; When the on-tube time period has passed, the third upper bridge arm switch and the first lower bridge arm switch are turned off, and the third lower bridge arm switch and the first upper bridge arm switch are turned on to complete the heating of the windings between different phases.

5. The method according to claim 1, characterized in that The step of detecting the rotor temperature by using the rotor operating state temperature model comprises: Get the comprehensive power loss; Establishing a rotor operating state temperature model according to the comprehensive power loss; The rotor temperature is obtained according to the rotor operating state temperature model.

6. The method according to claim 5, characterized in that The step of obtaining the comprehensive power loss comprises: Obtain coolant power loss, stator power loss to the environment, rotor and magnet power loss to the environment, and rotor heat loss; The comprehensive power loss is obtained according to the stator power loss, the power loss dissipated by the stator to the environment, the power loss dissipated by the rotor and the magnetic steel to the environment, and the rotor heat loss.

7. The method according to claim 6, characterized in that The steps of obtaining the coolant power loss, the stator power loss to the environment, the rotor and magnetic steel power loss to the environment, and the rotor heat loss include: The coolant power loss is obtained according to the coolant density, the cross-sectional area of ​​the cooling pipe, the coolant flow rate, the water inlet temperature and the water outlet temperature; According to the stator surface convection heat transfer area, the stator surface temperature, the ambient temperature and the preset convection heat transfer coefficient, the dissipated power loss of the stator to the environment is obtained; According to the convective heat transfer area of ​​the rotor surface, the rotor temperature at the first moment and the preset convective heat transfer coefficient, the power dissipation loss of the rotor and the magnetic steel to the environment is obtained; The rotor heat loss is obtained according to the specific heat capacity of the rotor material, the rotor mass, the rotor temperature at the second moment and the rotor temperature at the third moment.

8. The method according to claim 5, characterized in that The step of establishing a rotor operating state temperature model according to the comprehensive power loss comprises: Obtaining the specific heat capacity of the stator material, the stator mass, the stator temperature at the first moment, and the stator temperature at the second moment; A rotor operating state temperature model is established according to the specific heat capacity of the stator material, the stator mass, the stator temperature at the first moment, the stator temperature at the second moment, and the comprehensive power loss.

9. The method according to claim 1, characterized in that The step of stopping the winding heating and completing the battery pack heating according to the temperature protection strategy includes: Acquire a first preset temperature and a second preset temperature according to a temperature protection strategy, wherein the first preset temperature is greater than the second preset temperature; When any one of the rotor temperature, the insulated gate bipolar transistor temperature of the upper and lower bridge arm switches, and the negative temperature coefficient thermistor temperature is greater than the first preset temperature or the current temperature of the battery pack is greater than the second preset temperature, the winding heating is stopped and the battery pack heating is completed.

10. A battery pack heating device based on motor windings, characterized in that: The device comprises: A detection module, used for detecting the rotor temperature through a rotor operation state temperature model; A heating module, configured to, upon receiving a heating instruction, respectively open at least two of the bridge arm switches of the first phase, the second phase and the third phase of the power equipment according to the rotor temperature and the pipe opening strategy, so as to heat the windings between different phases; A transfer module, used for transferring heat generated when the winding is heated to a battery pack; The stop module is used to stop the winding heating according to the temperature protection strategy and complete the battery pack heating.

11. A battery pack heating device based on motor windings, characterized in that: The device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the motor winding-based battery pack heating method according to any one of claims 1 to 9.

12. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the battery pack heating method based on motor windings as described in any one of claims 1 to 9 are implemented.

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